FLIGHT International, 28 November 1974 745
Right, the pressurised Beech Baron BSSP
(see news item); below, one of Airtransit's
six Twin Otters at Rockliffe, Ottawa
;AIS TRANSPORT..
LIGHT
COMMERCIAL
& BUSINESS
a
The Airtransit operation
I N MAY 1971 the Federal Government of Canada directed its Ministry of Transport to plan, develop and evaluate a Stol commuter air system. The Ottawa-Montreal corridor
was chosen as the site for the trial, as competition from
every other mode of transportation exists along the route,
with more than 2*2 million persons travelling between the
two cities every year. Dense air traffic, to test the system's
compatibility with conventional air traffic, was a require
ment, as was the presence of a wide range of weather
conditions. The routeing had to lead to city-core areas
where "Stolports" could be built.
From the outset it was decided that the trial operation
had to test the complete Stol rapid-transit system from
city-centre to city-centre with minimum inconvenience and
maximum speed. Most of the pasengers would be business
people on day-return trips.
Criteria for both sites were space, convenience and
easy access to the centre as well as minimal noise dis
turbance to surrounding communities. The Twin Otter
requires only a 2,000ft runway and it was found possible
to construct the whole Stolport in only 44*2 acres. Of all
the sites considered in Ottawa the ex-RCAF base at Rock-
cliffe was judged the most suitable. In Montreal the
Victoria car park from the Expo 67 site was chosen and
the Stolport was constructed in less than a year.
Airtransit Canada, a wholly owned subsidiary of Air
Canada, was incorporated on June 19, 1973, to operate
the services for two years using six de Havilland Canada
Twin Otter Series 300s. The pilots were chosen in late
1973 and underwent extensive ground and simulator air
training courses. Several weeks of test flying demonstrated
to the residents that the Stolports would be less of a
noise nuisance at 500ft distance than a bus at 100ft.
The Twin Otters have been modified to improve safety
and Stol capability. Changes include high-capacity disc
brakes, anti-skid braking system, wing spoilers, propeller
de-icing, electrical and hydraulic system improvements,
emergency brakes, propeller auto-feather delay and
improved powerplant fire protection. Eleven larger seats
replace the original 20 and toilet facilities, a coat rack
and air-conditioning have been added.
The cruising altitude is between 3,000ft and 8,000ft and
as this is the height band of light aircraft and piston-
engined commercial aircraft the Twin Otters are fitted
with an area-navigation (RNav) system to allow them to
fly pre-selected routes off the airways to avoid congestion.
The RNav system selected allows certain routes to be
flown on autopilot by the insertion of a programmed card
into the system before the flight. Air traffic controllers
and pilots choose a flight plan that does not conflict with
other air traffic, and the requisite card is then fed into
the RNav computer.
Approaches are made at 6°-9° and the aircraft and
Stolports are fitted with Co-Scan MLS equipment. To
allow normal airways operation the aircraft are equipped
with full IFR instruments including flight recorder, elec
tric servo altimeter, radio altimeter, and an air data
acquisition system.
The trial started early in July and the Twin Otters
fly hourly from each of the two cities. The $20 fare covers
only the direct operating costs; there is a $24 million
annual Government subsidy.
Because of the size of the aircraft and the short flights
there are no cabin attendants. Baggage space on the air
craft is limited, but suitcases can be carried.
The system was designed to transport passengers city-
centre to city-centre, and ground transport to and from
the city cores is included in the fare. "Stolmobile" services
leave the Hotel Bonaventure, Montreal, 15min before
flight time and the Holiday Inn, Ottawa, 30min before
flight time. All seats have to be reserved.
Initial indications are that the Stol service is catching
on amongst the business community. The present petrol
problems are making the Stol service more popular; more
and more commuters prefer to travel city-centre to city-
centre at Airtransit's expense and to leave their own cars
at home.
B«ech pressurises the Baron Beech has introduced a
pressurised version of its Baron twin, FY1974 sales of
which showed a 27 per cent improvement in dollar terms
over 1973 figures. The six-seater B58P is powered by two
turbosupercharged 310 h.p. Continental engines and
deliveries are expected next spring.
Air Centre taken over The $2 • 1 million lawsuit filed
against Aerospatiale by US Corvette distributor Air Centre
of Oklahoma has been dropped following the assumption
of control of the distributor by the manufacturer. The
president of Air Centre is to leave and a new board is to
be elected.
More S-61s for British Airways British Airways Heli
copters has ordered three more Sikorsky S-61Ns for
delivery in the second half of next year.
Ambulance flying When four members of the crew of
the container ship Asiafreighter were poisoned by leaking
chemicals, Thurston Aviation's Islander and Navajo Chief
tain were called in to fly the casualties from RAF St
Mawgan to London.